最大累积率识别中国地表水中邻苯二甲酸酯类关键污染物和复合污染生态风险

邻苯二甲酸酯类物质(phthalic acid esters,PAEs)环境存在量大,研究表明其能对水生生物造成寿命减少、发育不良、细胞受损等负效应.因此,为保护水生生物,我国地表水中PAEs的生态风险需要科学评估.本文利用了风险商法(risk quotient,RQ)、最大累积率法(maximum cumulative ratio,MCR)、联合概率曲线法(joint probability curve,JPC)结合毒性当量的概念构建了三层级生态风险评价体系,借此评估了我国地表水中PAEs的分布情况与生态风险.结果显示,我国地表水中共检出19种PAEs,浓度范围为ND—5616.80μg·L^-1.邻苯二甲酸二(2-乙基)己酯(di(2-ethylhexyl)phthalate,DEHP)和邻苯二甲酸二丁酯(dibutyl phthalate,DBP)环境存在量最高,且DEHP为PAEs风险的主要贡献者.以DEHP为参照物,JPC的结果显示我国PAEs对5%生物造成急性影响的概率为6.25%—24.02%,造成慢性影响的概率为8.05%—27.79%.PAEs对我国水生生态系统,尤其是西北、东北、中部及华东地区存在较高的生态风险.

Identification the key pollutants of phthalic acid esters in surface water of China and ecological risk of mixture based on maximum cumulative ratio

Phthalic acid esters(PAEs)were detected generally in surface water.PAEs was reported to induce toxic effects on aquatic organisms such as life span reduction,dysplasia and cell damage.It is necessary to assess the ecological risk of PAEs posed to aquatic organisms in surface water of China.In this study,the three tiers ecological risk assessment system was established based on risk quotient,maximum cumulative ratio(MCR),joint probability curve(JPC)and the concept of toxic equivalence to evaluate the distribution and ecological risks of PAEs.In China,19 PAEs were detected in surface water.The concentration of them ranged from ND to 5616.80μg·L^-1.The environmental concentrations of di(2-ethylhexyl)phthalate(DEHP)and dibutyl phthalate were greater than others.DEHP were the main contributors to the risk posed by PAEs.According to the results of JPC,the probability that 5%of species will be acutely affected ranged from 6.25%to 24.02%,while that 5%of species will be chronically affected ranged from 8.05%to 27.79%with DEHP as reference.In summary,PAEs posed high ecological risk to aquatic ecosystem,especially in northwest,northeast,central and east China.